Push-button switch



Patented June 16, 1925.

UNITED STA res PATENT or s'rnn ERIC Lmnvann,

1,542,154 FICEI.

or prons, GERMANY.

PUSH-BUTTON SWITCH.

Application filed May 24, 1924. Serial No. 715,616.

paratively small costs. This push button switch can be .constructedqas asingle con tact breaker as well as a multiple contact breaker. The push button: switch cornprises an axially movable, non-rotatable spirally twisted member which on. its reciprocative movement;transmitsmotion to "a slotted operating member having ratchet teeth to operate a movablecontact. piece. Ratchet teeth are .alsoprovided on thecasing to lock the contact piece inposition after making or'breaking the connection of a circuit. The lastnamed ratchet teeth correspend in number to the ratchet teeth of the operating member.

The construction can be carried out in different ways. Of particular advantage is the construction which is hereafter described and illustrated. In this mode of construction there is the advantage, that the movable contact piece which has springy arms to make contact with. fixed contact pieces is not by these arms themselves locked in position after every operation and therefore does not slide over said ratchet teeth so that these arms of the contact piece are not so soon worn out or do not lose their flexibility, but in the construction shown by way of example special spring pawls are used which can be made of steel and are a not liable to lose the flexibility and therefore will never fail in operation.

Fig. 1 of the drawings is a section of the push button switch constructed according to the present invention. and

Fig. 2 is a plan of the switch the upper part or cover being removed.

The push button switch comprises a casing consisting of the lower member a and the upper member 7) forming a cover. The push button proper c is guided within. a suitably shaped opening at in the cover and has a shaft e of a flat cross section and spirally twisted. The utmost end f of this shaft is guided in a slot 0 in the bottom of the casing member at. Connecting terminals h are provided forconnecting the conductors and correspond in number to the electric circuits to be switched. Inthe construction shown two terminals are provided for a one way switch. They are electrically connected with the fixed. contact pieces z'the movable contact piece It having two arms adapted to make contact with the contact pieces c bears with its central disk shaped part 70 against a central boss 0', on the bottom of the lower casing member a. The central'i dislcshaped contact piece 70 in the construction shown by way of example has perforated flanges m through which projects a yoke wt preferably made of steel wire, and

the. prongs 0 of which yoke are bent to form pawls adapted tov slide over and to beengaged or locked in position by raltchetteeth 79 preferably formed on the bottom of the lower casing member a. On the disk-shaped contact; piece Z7 adish-shaped operating member q is adapted to slide having a slot 1* corresponding to the cross section of the shaft 6 of the button (2. The lower rim of the dish-shaped operating member is serrated to form ratchet teeth u corresponding in number to the ratchet teeth 79 formed in the bottom of the lower casino: member a. To properly guide the disk It a circular bushing s is let into the boss a. the disk in being provided with a corresponding central opening, the yoke 77, being bent in a central part to surround the bushing s, the curved part lying fiat on the disk 70. A spiral spring 15 is interposed between the push button proper 0 and the operating member (I. tending to press the operating member down on the disk Z1 toengage by its teeth the yoke a. when the push button 0 is pressed down. By so pushing the button down the spirally twisted shaft e causes the operating member (7 to rotatefor-the angle of the pitch of the teeth a and 79 respectively, the pawls 0 sliding from one tooth 79 over the next follow ing tooth 79 to be engaged by this tooth when the described movement is completed, thus locking the movable contact piece 70 either pitch of the teeth either to make or to break contact.

I claim: 1. A push button switch comprising a casing, contact pieces attached to the sides of the casing and a rotatable contact piece adapted to make and break contact between the said fixed contact pieces aspring' pressed push button having a flat spirally twisted 10 shaft prevented from rotation by being guided in aslot in the bottom of the casing, 'a slotted operating member engaged by said spirally twisted shaft to be'rotated thereby, when pushing down the ,button, ratchet teeth on a fixed part of the casing .and ratchet teeth on the said operating member, corigesponding in number to the first named ratchet teeth, a Sp ing pawl in connection with the rotatable contact piece and adapted to rotate with the operating member and to slide .over the fined ratchet teeth so as to :be rotated about an angle corresponding to the pitch ottheteeth by pushing inwardly the 'button and then locked position when the sa id operating member returns into its original position on the backward movement of the button by its p ine i 2. push button switch comprising a casing, contact pieces attached to the sides responding in number to the first named ratchet teeth, a spring pawl carried by the rotatable contact piece and adapted to be engaged by the first named ratchet teeth and to slide ,over the second ratchet teeth so as to be rotated about an angle corresponding to the pitch of the teeth by pushing inwardly the button and then looked in positionwhen the said operating memher'returns into ,itspriginal position on the backward movement of the button by its spring. 3. A push button switch according to claim 2, characterized in this that two spring pawls forming prongs of a yoke are carried the rotatable contact piece, the middle part being bent suitably guided to prevent rotation of the yoke, when the prongs slide on the locking ratchet teeth.

. STEN EBIC'LINDVALL- 

